Story perspectives

Machiavellianism, Psychopathy, Narcissism Show Distinct Brain Reductions

6/12/2026

Summary

Researchers Link Darktriad

Researchers linked dark triad traits to differences in a Journal of Neural Transmission study.
Machiavellianism and psychopathy both showed reduced gray matter in the left superior dorsolateral prefrontal cortex, with psychopathy also having lower anterior cingulate volume.
Subclinical narcissism showed reduced gray matter in the anterior cingulate, medial orbitofrontal cortex, superior temporal gyrus and insula, regions supporting moral decisions, empathy and reward learning, displaying a unique neural pattern.

Summary

Mielke Team Scans

Emilia L. Mielke’s team recruited 24 high-scoring and 27 low-scoring men via online ads and scanned their brains with MRI after medical interviews excluded psychiatric disorders.
Authors noted gray-matter volume does not equal functional efficiency and several results lost significance after correction.
Because the sample included only adult men, the study urges functional imaging with gender-inclusive participants to test whether the dark triad is a single factor or distinct traits.

Summary

Researchers Map Darktriad

The researchers reported reduced gray matter in the precentral gyrus of high-scoring dark-triad participants.
They also observed a smaller cerebellar crus II, a region linked to social cognition and facial-expression recognition.
Using voxel-based morphometry, the team mapped these precise gray-matter differences.
Authors presented the findings as a theoretical model tying neural loss to dark-triad traits, not as causal proof.

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Researchers Link Darktriad

Researchers linked dark triad traits to differences in a Journal of Neural Transmission study.
Machiavellianism and psychopathy both showed reduced gray matter in the left superior dorsolateral prefrontal cortex, with psychopathy also having lower anterior cingulate volume.
Subclinical narcissism showed reduced gray matter in the anterior cingulate, medial orbitofrontal cortex, superior temporal gyrus and insula, regions supporting moral decisions, empathy and reward learning, displaying a unique neural pattern.

1 / 3